1. Field of the Invention
The present invention relates to a two-part, low-backlash spindle nut for a screw transmission with two nut parts equipped with internal threads that interact with the external thread of the spindle of the screw transmission. The two nut parts on the spindle are loaded directed towards one another by at least one spring by torsion.
2. Discussion of Background Information
U.S. Pat. No. 4,433,590 shows a two-part spindle nut including two nut parts provided with internal threads preloaded on the external thread of the spindle by a spring, such that the nut parts are held against one another by a preloaded torque from the spring. The spring is wound on the cylindrical surfaces of the nut parts, whereby the spring wire ends are attached to the nut parts. The installation of this spindle nut entails considerable effort. The spring interferes on the surface of the nut parts requiring a protective cover, which increases the overall costs of the spindle nut. The preloading of the nut parts compensate for any wear of the threads on the spindle nuts and/or on the spindle, so that virtually no backlash occurs on the screw transmission during operation. However, the action of force of the spring will decrease during the life of the screw transmission, because the spring slackens due to stretching caused by thread wear.